And that's not something Nathan, 36, has taken for granted either.
"There were times that I wanted to go a little faster, push a little harder, but I always had the right people around me to stop me from doing that," Nathan said. "And I'm grateful now that they did that. We've always had plenty of time. I know it's not a lot of time when you look at how long it takes for a lot of people to come back from this, usually it's around that 16 months or so, but we worked hard. We're hoping that because I am a reliever that it won't take that long. We're hoping that come Spring Training, I'm ready to go."
Gardenhire, the Twins' training staff and a couple of Nathan's teammates were on hand Friday to watch the bullpen session. It was the second time that Nathan has thrown breaking pitches, so he acknowledged that he's still working to get comfortable with them, but he's been very pleased with the location of his fastball.
This weekend marks the end of Nathan's prescribed throwing program following the surgery. He's scheduled to play catch on Saturday and to throw another bullpen session on Sunday before heading back to his offseason home in Knoxville, Tenn. Nathan said he'll spend the next couple sessions primarily focusing on long toss and perhaps throwing one more bullpen session before he heads to Fort Myers, Fla., for Spring Training.
It's been a long and often arduous process to get to this point, and Nathan is anxiously looking forward to getting back on the field with his teammates for the first pitchers and catchers workout on Feb. 18. Although it's been more than a year since he's been on the field, Nathan has his mind set on showing his coaching staff that he's ready to resume his closer role.
"I'm shooting to be back on the baseball field and help this team win," said Nathan. "My plan is to go in and show them that I'm healthy and give them the confidence they've always had with me to put me in that role."
Nathan is planning to be ready to go full bore with all of the drills at the start of Spring Training. But Twins manager Ron Gardenhire stressed that while Nathan may be eager to get back in the mix with his teammates after missing all of last season, the coaching staff will be cautious with its four-time All-Star closer.
"We'll always err on the cautious side," Gardenhire said. "We'll try to do that with Nathan. We'll sit down and have our talk. I know he wants to be full bore because he's worked really hard. We'll have our talk soon and make sure we do the right thing."
Of course, there still might be some challenges along the way. One thing that sometimes takes awhile to return after surgery is a pitcher's velocity. Nathan said that his velocity has been coming along well for this point in the offseason, although he joked that his history of needing time to build up his velocity during Spring Training could come in handy now.
"Usually I'm not throwing harder than 86 mph in Spring Training anyway," Nathan said. "See all these years that I threw 86, everybody was so scared. But now I just set it up so now that I've had Tommy John surgery, they won't be scared when I'm only throwing that [this spring]."
The Twins have Matt Capps as a closing option should Nathan not be ready for the ninth inning at the start of the season. Capps was a Trade Deadline acquisition from the Nationals last season and took over the closing role from Jon Rauch. But before the Twins define any roles for the season, they'll wait to see how everything goes during the spring.
"If Nathan comes back and he's throwing like he did a couple years ago, then he'll probably be at the end of the ballgame," Gardenhire said. "And [pitching coach Rick Anderson] has already talked to Capps and he said, 'I'll do anything you want me to do.' That's exactly why we wanted this guy in our uniform.''
For Nathan, the focus is not necessarily on defining roles, but on making the club's bullpen as strong as it can be. Despite losing many of its key relievers from last season to free agency this winter (Matt Guerrier, Jesse Crain and Rauch), Nathan believes that the group can be a strength again.
"Everyone else is talking about [how] this team has question marks in the bullpen," Nathan said. "We feel like that's almost a slap in the face to us. We feel like we've done some pretty good things in this game. But we also know we have things to prove. ... We're excited about this year."